Hello. I've ordered a couple manuals (3 to date), all of which tell me how to remove things and give a cursory troubleshooting section on various systems, but not one of them explains in depth how my ignition and fuel system work.

Specifically, what sensors control what, at what temps they kick in, etc. I'm having a starting/idling issue that sometimes shows itself, and sometimes doesn't, and there's no clear reason why the car does what it does (not tied to outside temp, driving habits, etc).

Hello,
My 3.5 coupe had horrible drivability issues when I got it. Cleaning the trigger points and installing a Pertronix Ignitor ignition system completely cured my drivability issues.(assuming there is not something more seriously wrong with your system)
If you do an internet search of D-Jet you will find many useful articles on the FI. Installing the Pertronix system does away with the ignition amplifier and points-2 troublesome items.
Tony[8D]

I put in the Pertronix unit, replaced the injection points and a few sensors, as well as wires and plugs. The cold start system isn't working, so I'm looking for the cause. Otherwise, after the car starts, it runs pretty well. I intend to drive it from CO to CA, and once I get it here, I'll be replacing old hoses, vacuum lines and seals.